MIC2298

3.5A Minimum, 1MHz Boost High

Brightness White LED Driver

MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (

October 2007

M9999-101707-B

General Description

The MIC2298 is a high power boost-switching regulator

that is optimized for constant-current control. The MIC2298

is capable of driving up to 2 series 1A white LED for

photoflash, flashlight and other applications. The feedback

voltage is only 200mV, minimizing ballast power dissipa-

tion in constant-current control applications for improved

operating efficiency.

The MIC2298 has a brightness pin that allows for a

programmable torch mode as well full flash with a single

pin when driving high current LEDs.

The MIC2298 implements a constant frequency 1MHz

PWM control scheme to make the smallest possible

design.

The 2.5V to 10V input voltage range of MIC2298 allows

direct operation from 1- and 2-cell Li Ion as well as 3- to 6-

cell NiCad/NiMH/Alkaline battery sources. Maximum

battery life is assured with a low 1µA shutdown current.

The MIC2298 is available in a low profile 12-pin 3x3 MLF

®

package.

Data sheets and support documentation can be found on

Micrel’s web site at www.micrel.com.

Features

• 3.5A minimum switch current delivers at least 7W of

output power over-temperature

• 200mV ±10% feedback voltage

• 2.5V to 10V input voltage

• Output voltage up to 30V (max)

• Available output over-voltage protection (OVP)

• 1MHz operation

• Programmable output current

• <1% line regulation

• 1µA shutdown current

• Over temperature protection

• Externally programmable soft-start

• Under-voltage lockout (UVLO)

Applications

• Cell phones

• PDAs

• Digital cameras

• White LED flashlights

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Typical Application

Figure 1. High Power White LED Driver